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## Geometry (FL B.E.S.T.)

### Course: Geometry (FL B.E.S.T.)>Unit 5

Lesson 6: Parallel & perpendicular lines on the coordinate plane

# Classifying figures with coordinates

Use coordinates to determine the slopes of sides of a figure in order to classify it. Created by Sal Khan.

## Want to join the conversation?

• How exactly would taking the opposite reciprocal confirm that it is a 90 degree angle?
• how am I supposed to find the answer when he uses a graph every time, but none of the problems give you a graph to solve it on?
• Why do we have to learn geometry？
(1 vote)
• It has applications in all areas of mathematics and in all hard-sciences, also it's occasionally very beautiful (see penrose tiling and the golden ratio)
• At the start of the video I noticed that the points have related x and y values that go in some sort of shape that goes all the way around without crossing the other sides. did anybody else notice that? And does that also mean that any shape like that makes a rectangle?
(1 vote)
• There is a pattern, which has to do with the fact that the rectangle is actually a square.

Going clockwise around the square,
it just so happens to be that the sum of the 𝑥-coordinate of one corner and the 𝑦-coordinate of the next corner is constant,
and the difference between the 𝑦-coordinate of one corner and the 𝑥-coordinate of the next corner is also constant.

This is true for all squares.
(1 vote)
• how do people get this
(1 vote)